April 17, 2007

New York's state insect, the nine-spotted lady beetle, rediscovered in eastern U.S. after 14 elusive years

With habitat loss, pollution and climate changes, many creatures around the world are in decline. But Cornell researchers believe that the rediscovery of New York state's official insect, the nine-spotted lady beetle (Coccinella novemnotata or C9), promises a brighter future for this rare species.

The beetle was discovered in the Arlington, Va., backyard of Jeff and Leslie Perlman, parents of Cornell entomology student Jordan Perlman '10. Shortly before, the Perlmans had attended a presentation at Cornell on the plight of native ladybugs. With them at the time of the discovery were their younger son, Michael, and two neighborhood children and their mother.

"The importance of their discovery was not realized until later, and it is not clear who actually picked up the specimen," said John Losey, Cornell associate professor of entomology.

It was the first East Coast sighting of the insect in 14 years and only the seventh sighting in the last eight years across the nine-spotter's native range, which covers the United States and southern Canada. The specimen is now housed in the Cornell University Insect Collection.

The discovery is a success story for a fledgling Cornell citizen science program that helps train members of the public on how to find lady beetles in their locales and report their findings.

Cornell researchers have since applied for a $2 million National Science Foundation grant to educate youth about biodiversity and conservation and engage them in a lady beetle citizen science project, in which youth would search out and send digital images of lady beetles to Cornell and help keep an inventory of how many native and exotic species exist.

"We hope to find a viable C9 population, then we could start a colony and do some experiments to determine why they are declining," said Losey, lead author of a paper, co-authored by Perlman and Cornell extension associate Richard Hoebeke, on the discovery; the paper is now online and will be published in a forthcoming issue of the Journal of Insect Conservation. "There are probably many small populations dispersed around the country that are just flying below the radar," Losey said.

The beetle, noted for its white-fringed neck shields and four spots on each wing with a split spot in the middle of the wings, was one of the most common lady beetles through the 1970s, occupying a very wide range of habitats. But its numbers began declining in the 1980s. Before the latest sighting, it had last been seen in the Northeast in 1992.

"Unlike other rare species, we still don't know what areas they are likely to be in," said Losey. "It's not like a butterfly that is adapted to a rare plant. C9s had a wide range of habitats and prey."

Scientists suspect the nine-spotted beetle's decline may be related to competition from such invasive species as seven-spotted lady beetles and home-invading multicolored Asian beetles, whose arrivals and rise in numbers coincide with the nine-spotted beetle's decline. Other causes of decline could include loss of farmlands. Lady beetles are important economically because they prey on such crop pests as aphids.

In 2007, state legislators proposed a bill (that has yet to pass the Senate or be signed by the governor) to replace the nine-spotted lady beetle as the New York state insect with a smaller, pink lady beetle known as the pink-spotted lady beetle or 12-spotted lady beetle (Coleomegilla maculata). But Losey thinks changing the state beetle status would send the wrong conservation message. "The fact that it is in decline makes it the perfect symbol of New York's biodiversity," he said. "We should rally around this species like we did around the bald eagle."

Losey said Cornell students can learn more about conserving insect biodiversity in his Insect Conservation Biology course, and that anyone can participate in the citizen science program: http://instruct1.cit.cornell.edu/Courses/icb344/Lost_Ladybugs.htm.